Floating tank roof drain



Feb. i4, 95@ .,J. H. wxGGlNs FLoATING TANK RooF DRAN Filed Aug. 20, 1945 INVENTOR;

.JOHN H. 1G :Ns

" ATTORNEY Patented Feb. 14, 1950 "U NIT ED' STATES'- PATENT OFFICE This invention relates to floating tank' roof4 drains ofthe type that comprise a hose or.4 other suitable conduit that willl accomodate the rise' and fall of the floating roof, connected at itsI upper end to the' roof and having its' lower end extending through or connected to a stationary' part ofthe lower end portion of the tank;

One object'of my invention is to: provide a li'oat'- ing tank roof drain of the general kind. above mentioned, which is of such design or construction that it can be removed? and replaced without liability of subjecting the workmen performing the operation to danger resulting from gases* in thegasy space of the tank, sucnfor example', as inhelingL poisonous gases',y or causinggases to be ignited by a spark from the metali tools or parts used to attach the drain to the partV or parts with which it co-acts.

Another object is to provide an efficient means of. simple design and inexpensive construction for preventing an air pocket` from being created in the hose. or flexible conduit of. a floating tank roof drain ofthe general kind mentioned'.

And. still another object of. my invention is tov provide a'loati'ng. tank. roo! drain which is of such design or constructionthat, in the event the hose or other flexible' conduit' of same breaks in twoboth parts of said hose or'conduit can quickly and safely be removed from the' interior ofthe tank. Other objects and desirable features of my' invention4 will be hereinafter pointed out.

Figure 1 of the drawings is a vertical transverse sectional view of' a iloating' tank' roof equipped with a drain constructed in` accordance with' my' invention,

Figure 2 is a detail view, illustrating in side elevation,k one of the devices' on the underside of the floating' roof that is used to control theshape andv prevent excessive bending oi?v thehoseor' flexiblev conduit of the drain;

Figure 3y is a` sectional view of" the means usedto detachably connect the-- lower end portion of the hoseto/ the tank side wall; and

Figuree isI a sectional view of the means used to detachably connect the upper end portion of the hose tothe floatingy roof.

In the accompanying' drawings; which illustrate` onei'ormA of my invention?, A designates-J the side wall of a tank that is' adapted to hold liquid.V B1 designates the bottom of said tank, andlC designates av conventional floating roof that iloats` on` and is supportedlby the liquidl'Dfinftheltank.. Said floating' roof is' provided with a. drainl that leads.

from the top side of the roof, and which is ci? suolii design or construction, that it' willfaccornl 3- Claims; (C1. 2205-26) 2. mo'date the vertical movement of the roof' when; theroof rises and falls', due to' changes in the level. ofthe liquid D. In tlie' preferred'. forrn of' my' invention herein illustrated, said drain comprises a flexible hose l that is capable ofI floatingz in the liquid D', and the upper and lower ends oi said' nose are detachably connnected" to the roof C` and to the tank side wall A, respectively.

My' invention comprises (1)' An improved means for detachably con,-`

necting the lower end portion of the hose l" tothe. tank side wall A;

(2) An improved means for detachably con necti'ng the upper end' portion of said.v hose to the l floating roof C;

(3) A novel meansfor removing the hose from the interior of the tank in the event saidy hoseI breaks into two separate. pieces; and

(4) A novel meansfor controlling the shape"y of the hose so as to prevent an air pocket from being: created in the hose..

The means used to connectk the lower end portion of. the nose'to the tank side wall?, consists of a nipple 2v thatl is` preferably' cemented to the lower end portion of theA hose a llangeplate'i` 3' on said nipple rigidly connectedl to same by welding or in any other suitable'rnannner, a pad plate 6 on the exterior ofthe' tank sidewall A, arranged over anopening in said walls. that is of greater diameter than the flange plate 3, bolts or threaded studs* 5 rigidly attached by liquid-tight joints' to therfiange plate 3 and. projecting' outwardlyy Ironr4 same through an annular series of holes in they pad plate 6', a gasket. 4 between the plates 3 and 6, andl nuts 'l on th'ebolts 5 arranged on the outer.

The means used to detachably connect the upA per end. of thenose to the floating roof C.. consists of a nipple t2, preferably cemented tothe hose I and' welded or rigidly connected in any' other suitable way to a removable closure platel I0 that normally closes a-hole in the.v roof C",.and

stud bolts 9 for detachablyconnectng the closure plate; IllV to an annular supporting'y plate 8 at.. tached tothe roof,y so as to form a rim` for the L hole in the roof whichy the` plate ID normally n closes, said supporting plate Bibeing( provided in its topiside with blind,- tappedholes for thestuds 9, and:- a gaskety -i lbeingV arranged between; the, closure plate I0 and the supportingY plate 8, on?

which it bears, so as to produce a gas-tight joint between said parts.

In order to facilitate the removal from the tank of the two parts of a hose that has broken in two, a relatively thin corrosion-proof cable i4 is attached at one end to the nipple 2 at the lower end of the hose I, and attached at its other end to the nipple I2 at the upper end of the hose, Said cable I4 is the same length, or slightly longer than the hose, and is preferably attached to the hose in any suitable way at intervals of from live to ten feet. Subsequently, I will describe how said cable is used to remove a broken hose.

Unless the hose I is maintained in a certain approximate shape or position during the rise and fall of the roof C, a sharp, angular bend might form in the hose. This would be objectionable, because sharp bends cause rapid wear and deterioration, and they also produce air pockets which interfere with drainage. My improved drain comprises abutment members I3 and I3EL on the underside of the roof C, constructed and arranged so that when the roof moves upwardly towards the position represented by the broken line C', in Figure 1, the hose will assume the shape or position represented by the broken line I in said figure, and will effectively be prevented from bending at a sharp angle. Preferably, the members I3 and I3a are formed from metal rods attached to the underside of the roof and bent into the form of loops, whose horizontal cross pieces or hose contacting portions are Wide enough so that they will compensate for lateral flexing of the hose and always engage or contact the hose I, no matter which way said hose bends laterally as the roof rises and falls. They add little to the cost of the structure, but they eliminate the possibility of the hose bending into such a shape as to produce an air pocket.

The hose I is first installed from the inside of the tank by pushing the nipple 2 on the lower end of the hose outwardly through the pad plate 6 on the tank side wall, and simultaneously positioning the rigid bolts on the flange plate 3 in the openings provided for said bolts in the pad plate 6, the gasket 4 having proviously been positioned on the nipple 2 in engagement with the outer face of the ange plate 3. Thereafter, the nuts 1 of the bolts 5 are tightened by a workman located on the outside of the tank side wall. Afterthe upper end of the hose has been cemented to the nipple I2 on the closure plate Ill, said closure plate with the gasket l I positioned on the underside of same, is fastened to the supporting plate 8 on the roof by means of the stud bolts 9 which are inserted and tightened by a workman located on the top side of the roof.

If the hose breaks in two, a new hose can be installed and the two parts of the old hose can be withdrawn from the tank, without the necessity of ya workman entering the gas space of the tank, or reaching into the gas space and manipulating a wrench or other metal tool that might produce a ,spark in the gas space which would result in an explosion. To replace a broken hose, the level of the liquid in the tank is lowered to a point below the hole in the pad plate 6 on the tank Wall, as shown in broken lines in Figure l., wherein the reference character D designates the lowered liquid level. The flange plate 3 on the nipple 2 at the lower end of the hose is then released from the pad plate 5 by removing the nuts 1 on the bolts 5 which project outwardly through the pad plate 5, after which the workman, who is standing on the exterior of the side wall of the tank, attaches a trailer cable (not shown) to the nipple 2 at the lower end of the hose, said trailer cable being located on the exterior of the tank wall. A diierent workman, who is standing on the top side of the roof C, now unscrews the stud bolts Si and removes the closure plate I0 to which the upper end of the hose I is attached, and then withdraws from the tank the upper part of the broken hose that is attached to the nipple I2 on the closure plate ID, and also the lower part of the hose which is joined to the upper part of the hose by the cable I4, which, as previously stated, extends lengthwise of the hose and is attached to same at intervals along the length of the hose. This operation causes the trailer cable to be drawn into the tank through the hole in the pad plate 6 at the lower end of the tank, and then upwardly through the interior of the tank to the closure plate opening in the roof C, through which the two parts of the hose were withdrawn by the workman standing on the roof. Thereafter, the workman on the roof detaches the upper end of the trailer cable from the nipple 2 of the broken hose, and then attaches this end of the trailer cable to the nipple 2 of the new hose that is to be installed. At this time, the trailer cable extends from the closure plate opening in the roof to the hole in the pad plate 6 on the tank side wall, and the lower end of said trailer cable is located on the exterior of the tank side wall. The workman standing on the roof then inserts the nipple 2 and ange plate 3 of the new hose through the hole in the supporting plate 8 on the roof, and the workman standing on the ground adjacent the pad plate 5 on the tank side wall, then pulls downwardly on the trailer cable, so as to pull the nipple 2 at the lower` end of the hose outwardly through the nipple hole in the pad plate (i. If necessary, a rod or other device can be inserted into the end of the nipple 2 and turned or manipulated so as to line up the bolts 5 on the flange plate 3 with the holes provided for said bolts in the pad plate 6, after which said bolts can be drawn outwardly through the pad plate 5 sufficiently to enable the nuts 'I to be applied to same and then tightened so as to produce a liquid-tight joint between the flange plate 3 on the hose and the pad plate B on the tank wall. The nal step in the operation is to position the closure plate Ill on the supporting plate 8 on the roof and insert and tighten the stud bolts 9, so as to produce a gas and liquid-tight joint between the floating roof and the closure plate Ill, to which the upper end of the hose is attached.

A floating tank roof drain of the construction above described, overcomes the necessity of equipping the floating roof with a manhole for enabling a workman to enter or reach into the gas space of the tank during the operation of replacing a worn or broken hose, and hence, it protects workmen from danger, resulting from inhaling poisonous fumes, or resulting from an explosion caused by a spark from a metal tool that is manipulated inside of the gas space to release or tighten devices used to attach the drain hose to parts with which it co-acts. In my improved drain all of the operations employed in installing and removing the hose I are performed entirely on the exterior of the tank, without even reaching into the gas space of the tank, and the holes in the tank roof and tank side wall through which the hose is inserted and removed, are so small that the quantity of poisonous gases capable of escaping through same are not liable to be dangerous to workmen standing in the open. i

Also, the construction above described simplies the operation and reduces the time required to remove from the tank the two parts of a broken hose and to install a new hose and connect it by gas and liquid-tight joints to the floating roof and to the side wall of the tank. Also, as previously explained, my invention eliminates sharp, angular bends in the hose that produce rapid deterioration, or which create air pockets that interfere with drainage. The above described means for detachably connecting the hose to the structure, and the procedure for installing and replacing the hose, can be modilled without departing from the spirit of my invention, which, briey stated, consists in arranging a flexible conduit on the interior of a tank provided with a iloating roof, providing said conduit at its upper and lower ends with plates that form closures for openings in the roof and tank side wail, respectively, one of said plates being arranged on the interior ,of the structure and the other plate being arranged on the exterior of the structure, and providing means, operable from the exterior of the structure for detachably connecting said plates to parts of the structure which they overlap.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. The combination of a liquid storage tank, a roof for said tank that floats on the liquid in the tank, a ilexible drain conduit for said roof arranged on the interior of the tank and capable of lioatingln the liquid that sustains the roof, means on the roof for connecting the upper end of said drain to the roof, means on the lower end portion of the tank side wall for connecting the drain to said side wall, the conduit being free to flex intermediate the points where it is connected to the roof and to the tank side wall, and an abutment means for said conduit rigidly connected to the roof in stationary relationship with same and positioned between said conduit and the underside of the roof, said abutment means having no direct connection with the conduit and being provided with a contacting portion for said conduit located in a horizontal plane lower than the point of attachment of the upper end of the conduit with the roof, whereby said conduit will be prevented from assuming the form of an upwardly-disposed loop in which air can collect and interfere with the flow of the drainage from the top side of the roof through said conduit. 2. A structure of the kind described in claim 1, in which said abutment means is formed by a plurality of depending members on the underside of the roof arranged in spaced relation between the peripheral edge ofthe roof and the point of attachment of the upper end of the conduit with the roof and provided with horizontally-disposed conduit contacting portions of sufllcient width to compensate for lateral flexing of the conduit during the rise and fall of the roof.

3. A structure of the kind described in claim l, in which said conduit is provided with a cable or the like disposed longitudinally of same and attached at intervals along the length of the conduit.

' JOHN H. WIGGINS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,636,540 Wiggins July 19, 1927 1,668,792 Wiggins May 8, 1928 1,840,587 Kimbell Jan. 12, 1932 2,315,023 Stevenson Mar. 30, 1943 2,390,141 Wiggins Dec. 4, 1945 

